WAIT/Document/Multi.pm

#                              -*- Mode: Perl -*- 
# $Basename$
# $Revision: 1.2 $
# Author          : Marc Lehmann
# Created On      : June 2000
# Last Modified By: Ulrich Pfeifer
# Last Modified On: Fri Dec 29 12:56:35 2000
# Language        : CPerl

package WAIT::Document::Multi;

use WAIT::Document::Base;
use base 'WAIT::Document::Base';

=head1 NAME

WAIT::Document::Multi - access class that joins multiple access objects into a single one

=head1 SYNOPSIS

   use WAIT::Document::Multi;

   tie %acc, WAIT::Document::Multi::,
         access1 => <first access object>,
         access2 => <second acces sobject>;

=head1 DESCRIPTION

This WAIT access class accepts any number of "domain name" => "access
object" pairs and creates a unified view over all of these access objects.

The access objects must be actual objects, not tied hash references.

The document id's are generated by appending the domain name, a binary
zero and the document id of the underlying access object.

=cut

sub new {
   my $class = shift,
   my %unused;
   tie %unused, $class, @_;
}

sub TIEHASH {
   my $type = shift;
   my %acc = @_;
   my ($fst, %nxt);
   for (keys %acc) {
      $nxt{$_} = $fst; $fst = $_;
   }
   bless {
      acc => \%acc,
      fst => $fst,
      nxt => \%nxt,
   }, ref $type || $type;
}

sub FETCH {
   my $self = shift;
   my ($dom, $key) = split /\x00/, shift, 2;
   $self->{acc}{$dom}->FETCH($key);
}

sub FIRSTKEY {
   my $self = shift;
   my $dom = $self->{fst};
   "$dom\x00".$self->{acc}{$dom}->FIRSTKEY;
}

sub NEXTKEY {
   my $self = shift;
   my ($dom, $key) = split /\x00/, shift, 2;
   my $nxt = $self->{acc}{$dom}->NEXTKEY($key);
   unless ($nxt) {
      $dom = $self->{nxt}{$dom};
      return unless $dom;
      $nxt = $self->{acc}{$dom}->FIRSTKEY;
   }
   "$dom\x00$nxt";
}

=head1 AUTHOR

 Marc Lehmann <pcg@goof.com>
 http://www.goof.com/pcg/marc/

=cut

1;

1	# -- Mode: Perl --
2	# $Basename$
3	# $Revision: 1.2 $
4	# Author : Marc Lehmann
5	# Created On : June 2000
6	# Last Modified By: Ulrich Pfeifer
7	# Last Modified On: Fri Dec 29 12:56:35 2000
8	# Language : CPerl
9
10	package WAIT::Document::Multi;
11
12	use WAIT::Document::Base;
13	use base 'WAIT::Document::Base';
14
15	=head1 NAME
16
17	WAIT::Document::Multi - access class that joins multiple access objects into a single one
18
19	=head1 SYNOPSIS
20
21	use WAIT::Document::Multi;
22
23	tie %acc, WAIT::Document::Multi::,
24	access1 => <first access object>,
25	access2 => <second acces sobject>;
26
27	=head1 DESCRIPTION
28
29	This WAIT access class accepts any number of "domain name" => "access
30	object" pairs and creates a unified view over all of these access objects.
31
32	The access objects must be actual objects, not tied hash references.
33
34	The document id's are generated by appending the domain name, a binary
35	zero and the document id of the underlying access object.
36
37	=cut
38
39	sub new {
40	my $class = shift,
41	my %unused;
42	tie %unused, $class, @_;
43	}
44
45	sub TIEHASH {
46	my $type = shift;
47	my %acc = @_;
48	my ($fst, %nxt);
49	for (keys %acc) {
50	$nxt{$_} = $fst; $fst = $_;
51	}
52	bless {
53	acc => \%acc,
54	fst => $fst,
55	nxt => \%nxt,
56	}, ref $type \|\| $type;
57	}
58
59	sub FETCH {
60	my $self = shift;
61	my ($dom, $key) = split /\x00/, shift, 2;
62	$self->{acc}{$dom}->FETCH($key);
63	}
64
65	sub FIRSTKEY {
66	my $self = shift;
67	my $dom = $self->{fst};
68	"$dom\x00".$self->{acc}{$dom}->FIRSTKEY;
69	}
70
71	sub NEXTKEY {
72	my $self = shift;
73	my ($dom, $key) = split /\x00/, shift, 2;
74	my $nxt = $self->{acc}{$dom}->NEXTKEY($key);
75	unless ($nxt) {
76	$dom = $self->{nxt}{$dom};
77	return unless $dom;
78	$nxt = $self->{acc}{$dom}->FIRSTKEY;
79	}
80	"$dom\x00$nxt";
81	}
82
83	=head1 AUTHOR
84
85	Marc Lehmann <pcg@goof.com>
86	http://www.goof.com/pcg/marc/
87
88	=cut
89
90	1;
91